The present invention relates to a shift register, a data line driving circuit, a scanning line driving circuit, an electro-optical device, and an electronic apparatus.
A conventional electro-optical device, for example, a driving circuit of a liquid crystal device is composed of a data line driving circuit or a scanning line driving circuit for supplying a data line signal or a scanning signal to data lines or scanning lines arranged in an image display region at a predetermined timing.
The basic structures of the data line driving circuits are different to each other, depending on whether the input image signal is an analog signal or a digital signal. However, the data line driving circuit comprises a shift register for shifting a transfer signal which is initially supplied in a horizontal scan period in accordance with a clock signal in sequence.
As the shift register, Patent Document 1 discloses the structure having shift means and clock signal control means. The shift means has a plurality of cascade-connected shift unit circuits for shifting a start pulse in synchronization with a clock signal in order to output an output signal and for controlling the transfer direction of the start pulse based on a transfer direction signal indicating a transfer direction. The clock signal control means has a plurality of control unit circuits which are provided to correspond to the shift unit circuits to control the supply of the clock signal to each shift unit circuit.
In other words, in the conventional shift register, the shift unit circuits one-to-one correspond to the control unit circuits.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2003-308049 (claim 1).